Finding a truly economical way to cool a house in the hot summer months can rescue the family budget. Portable evaporative (swamp) coolers can achieve that aim in the right circumstances as this article goes on to explain.

I've already mentioned the most common ways of maintaining a comfortable indoor climate in a dwelling in my article on climate control in the home (see below). However, I wanted to expand on the economical and financial benefits that can be achieved by opting for an evaporative cooling solution rather than going the route of air conditioning to provide the temperature changes.

Watching the Pennies

We all know that rising energy costs are making it ever tougher to make ends meet when the family budget gets stretched to breaking point by continuous use of a home's air conditioning in summer. That's because this type of cooling measure uses a lot of energy to produce the lower indoor temperatures we need for comfortable living.

Even small portable AC units can consume upwards of 2-3 kilowatts of power, so a cheaper solution is desirable where possible. Enter the swamp cooler!

Evaporative (swamp) coolers use only a fraction of the energy of air conditioners to produce just as much cold air in the right circumstance. With a medium sized swamp cooler running on as little as 100 watts or so, this can represent 1/20th of the energy consumption and likewise, 1/20th of the costs!

No Vent Needed

The other big advantage of this type of appliance is that it does not need to be vented to the outside. That can be a real convenience if you have only the one unit and need to wheel it from room to room as you move around your home.

That's because there is no trailing plastic vent tube to undock from its window venting kit when you move it as with portable AC units. For this reason, these devices are often mistakenly referred to as portable air conditioners that are vent free.

Why doesn't everyone go out and but these appliances?

Humidity is the Enemy

Unfortunately, these particular cooling appliances do not work very well when the air is humid. The reason for this is because of the way that they work.

Cooling by evaporation occurs when hot, dry air is drawn through a damp medium, which absorbs the heat and the resulting chilled air is then circulated around the room. The hot air entering such a device needs to be dry because on its way out it becomes humidified.

When the cold, humid air created in the swamp cooler circulates round the room the temperature drops by up to 20-25 F. But if the air in the room is already saturated with moisture (50-60% humidity or higher) the air passing through the damp membrane in the device is not cooled because not much more moisture can be added to it and the heat is not absorbed so effectively.

Dry Atmosphere

For this reason, these types of cooling machines are best used in dry climates such as desert or inland areas that are a long way from large bodies of water. Coastal areas have naturally humid air from the sea and the same goes for towns that are by large lakes or wide, voluminous rivers and are not suitable locations for this kind of air cooling.

If you live in an area with high humidity, you are limited in your choice of climate control to regular (and expensive) air conditioning, unfortunately.